Template synthesis of armchair-edge graphene nanoribbons inside carbon nanotubes

Abstract

We developed a template synthesis for armchair-edge graphene nanoribbons inside single-wall carbon nanotubes (SWCNTs). A direct vapor-phase reaction with 10,10′-dibromo-9,9′-bianthryl furnished armchair graphene nanoribbons with a width of seven carbon atoms (7-AGNRs) through dehalogenative polymerization and dehydrogenation cyclization within the cavities of the SWCNTs. High-resolution transmission electron microscopy studies revealed that the 7-AGNRs were twisted inside the nanotubes, and that their conformations sensitively changed with the diameter of the SWCNTs. The optical band gap of 7-AGNRs encapsulated in SWCNTs was estimated to be 2.1 eV from absorption spectroscopy measurements.